ICU  Instrument.Comparator.Unit 
ID  Identifier 
IDC  Indicator.Display/Control 
IDE  Integrated.Development.Environment 
Ident  The.action.of.the.transponder.transmitting.an. 
extra pulse along with its identification code (at 
the request of a controller). 
IDI  Initial Domain Identifier 
IDG  Integrated.Drive.Generator 
IDM  Integrated.Decision.Making 
IDP  Initial.Domain.Part 
IDRP  Inter-Domain.Routing.Protocol 
IDS  (.1.).Ice.Detection.System.. 
(.2.).Integrated.Display.System.. 
(.3.).Information.Display.System 
IDU  Interactive.Display.Unit 
IEC  IAPS.Environmental.Control.Module 
IED  Insertion.Extraction.Device 
IEEE  Institute.of.Electrical.and.Electronics.Engineers 
IEPR  Integrated.Engine.Pressure.Ratio 
IETM  Interactive.Electronic.Training.Manual 
IF(if)  Intermediate Frequency. A frequency to which 
a.signal.is.shifted.as.an.in-between.step.in.the. 
reception.or.transmission.of.a.signal. 
IFALPA  International.Federation.of.Airline.Pilots. 
Association 
IFATCA  International Federation of Air Traffic Controllers’ 
Associations 
IFE  In-Flight.Entertainment 
IFPS  Integrated.Initial.Flight.Plan.Processing.System 
IFR  Instrument.Flight.Rules 
IFRB  International Frequency Registration Board 
IGA  Intermediate.Gain.Antenna 

IGES IGIA IGS IGV ILM ILS
IM
IMA IMAS IMC IMG IMI IMOK IMPATT Diode
IMS IMU

INBD
IND
Indicated Altitude INFO in.hg. INIT INJ INMARSAT
Standardized.Graphics.Exchange.File Interagency.Group.on.International.Aviation Integrated.Ground.Software Inlet.Guide.Vane Independent.Landing.Monitor Instrument.Landing.System..The.system.provides.
lateral,.a.long-course.and.vertical.guidance.to.
aircraft.attempting.a.landing. Inner.Marker.Beacon:.When.present,.MB.used. in.conjunction.with.ILS,.intercepts.glideslope. approximately.100.feet.above.touchdown.
Integrated.Modular.Avionics Integrated.Mission.Avionics.System Instrument.Meteorological.Conditions Implementation.Management.Group
Imbedded Message Identifier I’m Okay
Impact.Avalanche.and.Transmit.Time..This. type.of.diode,.when.mounted.in.an.appropriate. cavity,.produces.microwave.oscillations.and.